|...as the cause of my troubles.
Did I remove the plenum? Yes. And replace with OEM orificed PCV pipes? Yes (I sent you an e-mail with pics :-). I verified that my old gauge was accurate by comparing it to a new one. The new gauge had no fluctuations and measure a comperable vacuum value. The injectors are all new as are the injector insulators and plenum gasket so I doubt there are leaks there, at least I'm not hearing anything from there. I was very careful during the reinstall.
I'm starting to doubt that the EGR valve is my problem although it is leaking. Checked the valve operation last night and it works. The lack in power seems to be a function of rpm and not throttle position, ie. with WOT a low rpm there would be minimal vacuum as the plenum opens up to near ambient pressure and the leak coming through the EGR valve stem would become minimal but that's where I notice a lack of power. Any other ideas?